1. Field of the Invention
The present invention relates to a mobile terminal device having a removable external output device, a computer-readable recording medium, and a computer data signal.
2. Description of the Related Art
Generally, when the plug of a head phone as an external output device is plugged out from a jack section of a speaker embedded type audio device while a user is listening to music, a news program, or the like with the head phone being connected thereto, a large volume sound is suddenly generated from an embedded speaker.
As disclosed in, for example, Unexamined Japanese Patent Application KOKAI Publication No. H10-145884, there is known a technology which suppresses the volume of the embedded speaker at an appropriate level when the head phone is plugged out from the audio device and audio output is switched over to the embedded speaker, and enables adjustment of the volume to a desired level by a later operation of the user.
The foregoing technology switches over the audio output to the embedded speaker so that the user can consecutively listen to music to which the user has been listening so far even if the head phone is plugged out. Accordingly, even if the volume when the head phone is plugged off is adjusted to an appropriate level, it bothers people nearby in a public place like in a train. To overcome this problem, the volume level should be automatically adjusted to “0 (mute)” at the time of switching over from the head phone to the embedded speaker.
In this case, however, because it becomes a mute state until the head phone is reconnected, in a case where the user is listening to a broadcast program in real time, for example, the user fails to hear the broadcast contents during a time from plugging off of the head phone to reconnection thereof.
In a case where the head phone is plugged off during the user is listening to recorded contents, so that the mode becomes a mute state, the user needs to do a reverse operation to adjust a reproduction start position in order to listen to recorded contents the user has missed. It is, however, very difficult to accurately reverse the recorded contents to the position of the missed part, and if it is not accurately reversed, the user may fail to hear some of the contents the user has missed again.